In general, in a maritime search and rescue system, an EPIRB device used for position identification and rescue of a vessel in the event of maritime disaster includes an EPIRB terminal and a housing for installing the EPIRB terminal in a vessel, for example, a container. The EPIRB terminal is installed in the vessel through the housing. Before the vessel sinks under the sea and reaches a predetermined depth of water, for example, 4 m under the sea, the housing is automatically separated from the vessel or container and rises to the surface of the water. The EPIRB terminal transmits a distress signal to a satellite, for example, a COSPAS-SARSAT satellite, at a predetermined period.
The COSPAS-SARSAT satellite receives the distress signal from the EPIRB terminal, and transmits the received distress signal to a local terminal located in a region nearest to the EPIRB terminal, for example, a Local User Terminal (LUT). The LUT calculates and estimate the distress position of the vessel equipped with the EPIRB terminal, and transmits the distress signal to a Mission Control Center (MCC) of a corresponding area. The MCC identifies the position of the distressed vessel through the distress signal, and rescues the distressed vessel.
As described above, in the EPIRB device, the EPIRB terminal is installed in the vessel by the housing, and the EPIRB terminal is separated from the vessel by the sensing operation of sensors included in the EPIRB terminal, for example, a water pressure sensor and a water sensor, rises to the surface of the water, and automatically broadcasts the distress signal. At this time, the water pressure sensor and the water sensor perform the sensing operation when the EPIRB terminal enters the water. However, in a case in which water penetrates into the EPIRB terminal due to various environmental factors in the vessel equipped with the EPIRB terminal and on the sea, the water pressure sensor and the water sensor may malfunction.
Even when the water pressure sensor and the water sensor included in the EPIRB terminal malfunction, the EPIRB terminal broadcasts the distress signal, and the COSPAS-SARSAT satellite receives the distress signal from the EPIRB terminal, and transmits the received distress signal to the LUT located in a region nearest to the EPIRB terminal, the LUT calculates and estimate the distress position of the vessel equipped with the EPIRB terminal, and transmits the distress signal to the MCC of the corresponding area, and the MCC identifies the position of the distressed vessel through the distress signal, and rescues the distressed vessel.
In other words, the maritime search and rescue system normally performs the maritime search and rescue operation, without regard to the malfunction of the water pressure sensor and the water sensor included in the EPIRB terminal. In particular, a lot of resources are wasted by the wrong transmission of the distress signal caused by the malfunction of the EPIRB terminal. For example, according to the announcement of the COSPAS-SARSAT Secretariat in 2009, it was confirmed that about 96% of the distress signals broadcast from the EPIRB terminals was wrongly transmitted, and thus, a lot of resources was being wasted globally.
Therefore, there is a need for minimizing the malfunction of the EPIRB terminal in the maritime search and rescue system and the wrong transmission of the distress signal caused by the malfunction of the EPIRB terminal.